Radiographic image processing apparatus, radiographic image processing method, and radiographic image processing program

ABSTRACT

A detection unit detects a region of a surgical tool in a radiographic image of a patient. In a case in which the surgical tool is detected, a display control unit displays the radiographic image on a display unit such that the detected region of the surgical tool is highlighted.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application claims priority under 35 U.S.C. § 119 toJapanese Patent Application No. 2019-177642 filed on Sep. 27, 2019. Theabove application is hereby expressly incorporated by reference, in itsentirety, into the present application.

BACKGROUND OF THE INVENTION Technical Field

The present disclosure relates to a radiographic image processingapparatus, a radiographic image processing method, and a radiographicimage processing program.

Related Art

Various surgical tools, such as gauze for suppressing bleeding, a threadand a needle for sewing up a wound, a scalpel and scissors for incision,a drain for draining blood, and forceps for opening incision, are usedin a case in which a surgical operation is performed for a patient. Thesurgical tools may cause serious complications in a case in which theyremain in the body of the patient after surgery. Therefore, it isnecessary to check that no surgical tools remain in the body of thepatient after surgery. However, there is a possibility that theremaining surgical tool will be overlooked by visual confirmation in anexhausted state after surgery.

Therefore, a method has been proposed which detects a foreign materialin an image of a patient and displays the foreign material so as to behighlighted. For example, JP2017-202310A discloses a method that, in acase in which a foreign material, such as metal, is detected in a CTimage of a patient, presents the detected foreign material on the image.Further, JP2018-517950A discloses a method that acquires a video imageof a surgical site with a camera and displays a non-tissue region, suchas gauze, in the video image so as to be highlighted.

However, CT images are not capable of being captured in an operatingroom and it is necessary to move a patient to an imaging room for CTimaging after surgery. Therefore, even in a case in which a foreignmaterial is found in the body of the patient by the method described inJP2017-202310A, surgery needs to be performed again in order to removethe foreign material, which imposes a heavy burden on the patient. Inaddition, gauze is used to be pushed into the body of the patient and isstained with blood. Therefore, it is difficult to find gauze using thevideo image acquired by the camera as in the method described inJP2018-517950A. Further, in many cases, the surgical field is blocked bythe operator. Therefore, it is difficult to always ensure the surgicalfield in order to acquire a video image. For this reason, there is apossibility that a surgical tool will remain in the body of the patientafter the surgery in the method described in JP2018-517950A.

SUMMARY OF THE INVENTION

The present disclosure has been made in view of the above-mentionedproblems and an object of the present disclosure is to provide atechnique that can reliably prevent a surgical tool from remaining in abody of a patient after surgery, without imposing a burden on thepatient.

According to the present disclosure, there is provided a radiographicimage processing apparatus comprising: a detection unit that detects aregion of a surgical tool in a radiographic image of a patient; and adisplay control unit that, in a case in which the surgical tool isdetected, displays the radiographic image in which the detected regionof the surgical tool has been highlighted on a display unit.

The “radiographic image” in the present disclosure means atwo-dimensional image which is a fluoroscopic image of a subjectacquired by irradiating the subject with radiation. The radiographicimage may be a still image or a moving image. For example, theradiographic image may be acquired by a portable radiation detector. Insome cases, the operator performs surgery while observing theradiographic image of the patient using a C-arm fluoroscopic apparatus.In this case, the radiographic image may be acquired by the C-armfluoroscopic apparatus.

The radiographic image processing apparatus according to the presentdisclosure may further comprise an image processing unit that performsimage processing for checking the surgical tool on the radiographicimage to derive a processed radiographic image.

In the radiographic image processing apparatus according to the presentdisclosure, the radiographic image in which the detected region of thesurgical tool has been highlighted and which is displayed on the displayunit by the display control unit may be the processed radiographicimage.

In the radiographic image processing apparatus according to the presentdisclosure, the display control unit may display, on the display unit,the radiographic image before the image processing for checking thesurgical tool. The image processing unit may derive the processedradiographic image and the detection unit may start a process ofdetecting the region of the surgical tool in response to a command todetect the region of the surgical tool. In a case in which the processedradiographic image is derived, the display control unit may display theprocessed radiographic image on the display unit, instead of theradiographic image before the image processing or together with theradiographic image before the image processing. After the process ofdetecting the region of the surgical tool ends, the display control unitmay display the radiographic image in which the region of the surgicaltool has been highlighted on the display unit.

In the radiographic image processing apparatus according to the presentdisclosure, the display control unit may further display theradiographic image in which the detected region of the surgical tool hasbeen highlighted on another display unit that has a larger size and/or ahigher resolution than the display unit.

In the radiographic image processing apparatus according to the presentdisclosure, the display control unit may further display theradiographic image before the image processing, the processedradiographic image, and the radiographic image in which the detectedregion of the surgical tool has been highlighted on another display unitthat has a larger size and/or a higher resolution than the display unit.

In the radiographic image processing apparatus according to the presentdisclosure, in a case in which the surgical tool is not detected, thedisplay control unit may notify the fact.

In the radiographic image processing apparatus according to the presentdisclosure, the radiographic image may be acquired by a portableradiation detector or an imaging apparatus that is installed in anoperating room for performing surgery on the patient.

In the radiographic image processing apparatus according to the presentdisclosure, the detection unit may include a discriminator trained so asto discriminate the region of the surgical tool in an input radiographicimage.

In the radiographic image processing apparatus according to the presentdisclosure, the surgical tool may include at least one of gauze, ascalpel, scissors, a drain, a needle, a thread, or forceps.

In the radiographic image processing apparatus according to the presentdisclosure, at least a portion of the gauze may include a radiationabsorbing thread.

According to the present disclosure, there is provided a radiographicimage processing method comprising: detecting a region of a surgicaltool in a radiographic image of a patient; and in a case in which thesurgical tool is detected, displaying the radiographic image on adisplay unit such that the detected region of the surgical tool ishighlighted.

In addition, a program that causes a computer to perform theradiographic image processing method according to the present disclosuremay be provided.

Another radiographic image processing apparatus according to the presentdisclosure comprises a memory that stores commands to be executed by acomputer and a processor that is configured to execute the storedcommands. The processor performs: a process of detecting a region of asurgical tool in a radiographic image of a patient; and a process of, ina case in which the surgical tool is detected, displaying theradiographic image on a display unit such that the detected region ofthe surgical tool is highlighted.

According to the present disclosure, it is possible to reliably preventa surgical tool from remaining in a body of a patient after surgery,without imposing a burden on the patient.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram schematically illustrating a configuration ofa radiography system to which a radiographic image processing apparatusaccording to a first embodiment of the present disclosure is applied.

FIG. 2 is a block diagram schematically illustrating a configuration ofa radiographic image management system.

FIG. 3 is a diagram schematically illustrating a configuration of theradiographic image processing apparatus according to the firstembodiment.

FIG. 4 is a diagram illustrating gauze.

FIG. 5 is a diagram illustrating a radiographic image including asurgical tool.

FIG. 6 is a diagram illustrating a display screen for a radiographicimage in which a region of a surgical tool is highlighted.

FIG. 7 is a diagram illustrating the display screen for the radiographicimage in which the region of the surgical tool is highlighted.

FIG. 8 is a diagram illustrating the display screen for the radiographicimage in which the region of the surgical tool is highlighted.

FIG. 9 is a diagram illustrating a notification screen in a case inwhich the region of the surgical tool is not detected.

FIG. 10 is a flowchart illustrating a process performed in the firstembodiment.

FIG. 11 is a diagram schematically illustrating a configuration of aradiographic image processing apparatus according to a secondembodiment.

FIG. 12 is a flowchart illustrating a processing performed in the secondembodiment.

FIG. 13 is a diagram illustrating a radiographic image display screen.

FIG. 14 is a diagram illustrating a processed radiographic image displayscreen.

FIG. 15 is a diagram illustrating a display screen for a processedradiographic image in which a region of a surgical tool is highlighted.

FIG. 16 is a diagram illustrating a display screen on which aradiographic image and a processed radiographic image are displayedtogether.

FIG. 17 is a diagram schematically illustrating a configuration of aradiographic image processing apparatus according to a third embodiment.

FIG. 18 is a flowchart illustrating a process performed in the thirdembodiment.

FIG. 19 is a diagram schematically illustrating a configuration of aradiographic image processing apparatus according to a fourthembodiment.

FIG. 20 is a flowchart illustrating a process performed in the fourthembodiment.

DETAILED DESCRIPTION

Hereinafter, embodiments of the present disclosure will be describedwith reference to the drawings. FIG. 1 is a block diagram schematicallyillustrating a configuration of a radiography system to which aradiographic image processing apparatus according to a first embodimentof the present disclosure is applied. As illustrated in FIG. 1, aradiography system 100 according to the first embodiment acquires aradiographic image of a subject as a patient after a surgical operationand detects a surgical tool included in the radiographic image. Theradiography system 100 according to this embodiment comprises an imagingapparatus 1 and a console 2 which is the radiographic image processingapparatus according to this embodiment.

The imaging apparatus 1 irradiates a radiation detector 5 with radiationwhich has been emitted from a radiation source 4, such as an X-raysource, and transmitted through a subject H to acquire a radiographicimage G0 of the subject H that lies supine on an operating table 3. Theradiographic image G0 is input to the console 2 which is theradiographic image processing apparatus.

The radiation detector 5 can repeatedly perform the recording andreading of a radiographic image and may be a so-called direct-typeradiation detector that directly receives the emitted radiation andgenerates charge or a so-called indirect-type radiation detector thatconverts radiation into visible light and then converts the visiblelight into a charge signal. As a method for reading a radiographic imagesignal, it is desirable to use a so-called thin film transistor (TFT)reading method which turns on and off a TFT switch to read aradiographic image signal or a so-called optical reading method whichemits reading light to read a radiographic image signal. However, thepresent disclosure is not limited thereto and other methods may be used.

The radiation detector 5 is a portable radiation detector and isattached to the operating table 3 by an attachment portion 3A that isprovided in the operating table 3. The radiation detector 5 may be fixedto the operating table 3.

A display unit 6 and an input unit 7 are connected to the console 2. Thedisplay unit 6 consists of display, for example, a cathode ray tube(CRT) or a liquid crystal display and assists the input of aradiographic image acquired by imaging and various kinds of datanecessary for processes performed by the computer 2. The input unit 7consists of, for example, a keyboard, a mouse, or a touch panel.

A radiographic image processing program according to this embodiment isinstalled in the console 2. In this embodiment, the console 2 may be aworkstation or a personal computer that is directly operated by anoperator or a server computer that is connected to the console through anetwork. The radiographic image processing program is stored in astorage device of the server computer connected to the network or anetwork storage so as to be accessed from the outside and is downloadedand installed in the computer on demand. Alternatively, the radiographicimage processing program is recorded on a recording medium such as adigital versatile disc (DVD) or a compact disc read only memory(CD-ROM), is distributed, and is installed in the computer from therecording medium.

The radiography system according to this embodiment forms a portion of aradiographic image management system illustrated in FIG. 2. Asillustrated in FIG. 2, in the radiographic image management systemaccording to this embodiment, the radiography system 100 including theimaging apparatus 1 and the console 2 and a picture archiving andcommunication system (PACS) 101 are connected through a network 102 suchthat they can communicate with each other.

FIG. 3 is a diagram schematically illustrating the configuration of theradiographic image processing apparatus implemented by installing, forexample, the radiographic image processing program according to thefirst embodiment in the console 2. As illustrated in FIG. 3, theradiographic image processing apparatus comprises a central processingunit (CPU) 11, a memory 12, and a storage 13 as a standard computerconfiguration.

The storage 13 consists of a storage device, such as a hard disk or asolid state drive (SSD), and stores various kinds of informationincluding an imaging program for driving each unit of the imagingapparatus 1 and the radiographic image processing program. In addition,the radiographic image acquired by imaging is stored in the storage 13.

The memory 12 temporarily stores, for example, the radiographic imageprocessing program stored in the storage 13 in order to cause the CPU 11to perform various processes. The radiographic image processing programdefines the following processes as processes to be performed by the CPU11: an image acquisition process that irradiates the radiation detector5 with radiation, which has been emitted from the radiation source 4 andthen transmitted through the subject H, to acquire the radiographicimage G0; a detection process that detects a region of a surgical toolin the radiographic image; and a display control process that displaysthe radiographic image on the display unit 6 such that the detectedregion of the surgical tool is highlighted in a case in which thesurgical tool is detected.

The CPU 11 performs the above-mentioned processes according to theradiographic image processing program such that the console 2 functionsas an image acquisition unit 21, a detection unit 22, and a displaycontrol unit 23.

The image acquisition unit 21 drives the radiation source 4 to irradiatethe subject H that has undergone surgery with radiation and detects theradiation transmitted through the subject H using the radiation detector5 to acquire the radiographic image G0. In this case, the imageacquisition unit 21 sets imaging conditions, such as the type of targetand filter used in the radiation source 4, an imaging dose, a tubevoltage, and a SID.

The detection unit 22 detects the region of the surgical tool in theradiographic image G0. For the detection, a discriminator 30 thatdiscriminates the region of the surgical tool included in theradiographic image G0 in a case in which the radiographic image G0 isinput is applied to the detection unit 22. In a case in which the targetradiographic image G0 is input to the detection unit 22, the detectionunit 22 directs the discriminator 30 to discriminate the region of thesurgical tool included in the radiographic image G0, thereby detectingthe region of the surgical tool.

Here, the discriminator 30 is constructed by training a machine learningmodel using a radiographic image including a surgical tool as trainingdata. In this embodiment, it is assumed that gauze is used as thesurgical tool.

FIG. 4 is a diagram illustrating gauze. As illustrated in FIG. 4, gauze40 is a plain-woven cotton fabric and a radiation absorbing thread 41 iswoven in a portion of the gauze 40. Cotton yarn transmits radiation andthe radiation absorbing thread 41 absorbs radiation. Therefore, theradiographic image of the gauze 40 includes only the linear radiationabsorbing thread 41. Here, during surgery, the gauze 40 is rolled andinserted into the human body in order to absorb blood. Therefore, in acase in which the gauze 40 is present in the human body, as illustratedin FIG. 5, a gauze image 42 which is the image of the gauze 40 includedin the radiographic image G0 represents a state in which the radiationabsorbing thread 41 is curled.

In a case in which the detection unit 22 detects the region of thesurgical tool from the radiographic image G0, the display control unit23 displays the radiographic image G0 on the display unit 6 such thatthe region of the surgical tool is highlighted. FIG. 6 is a diagramillustrating a display screen for a radiographic image in which theregion of the surgical tool is highlighted. As illustrated in FIG. 6, aradiographic image GH0 obtained by superimposing a mask 51 on the regionof the surgical tool included in the radiographic image G0 such that theregion of the surgical tool is highlighted is displayed on a displayscreen 50. The mask 51 is illustrated in white in FIG. 6. However, themask 51 may be colored. Further, the region of the surgical tool may behighlighted by superimposing a mark 52, such as an arrow or an asterisk,in the vicinity of the region of the surgical tool as illustrated inFIG. 7 or by surrounding the region of the surgical tool with a frame 53as illustrated in FIG. 8, instead of adding the mask 51. Here, theradiographic image GH0 in which the region of the surgical tool has beenhighlighted may be displayed on the display unit 6 by superimposing themask 51, the mark 52, and the frame 53 (hereinafter, referred to as amask and the like) on the radiographic image G0. In addition, a processof adding the mask or the like may be performed on the radiographicimage G0 to separately generate the radiographic image GH0 in which theregion of the surgical tool has been highlighted and the radiographicimage GH0 may be displayed on the display unit 6.

In addition, in a case in which the radiographic image GH0 in which theregion of the surgical tool has been highlighted is displayed on thedisplay unit 6, image processing for display, such as a gradationconversion process or a density conversion process, may be performed onthe radiographic image G0 in order for the operator to easily observethe displayed radiographic image GH0. The display control unit 23 mayperform the image processing for display or an image processing unit forperforming the image processing for display may be separately provided.In a case in which the image processing for display is performed on theradiographic image G0, the detection unit 22 may detect the region ofthe surgical tool from the radiographic image G0 subjected to the imageprocessing for display.

In addition, in a case in which the detection unit 22 does not detectthe region of the surgical tool from the radiographic image G0, thedisplay control unit 23 notifies the fact. FIG. 9 is a diagramillustrating a notification screen in a case in which no surgical toolsare detected. As illustrated in FIG. 9, a message 61 of “No surgicaltools have been detected.” is displayed on a notification screen 60 soas to be superimposed on the radiographic image G0. Instead of themessage 61, for example, an icon or a mark indicating that no surgicaltools have been detected may be displayed. Further, the turn-on andturn-off the display of the message 61 may be switched in response to acommand from the input unit 7.

Next, a surgical tool region detection process according to the firstembodiment will be described. FIG. 10 is a flowchart illustrating thedetection process performed in the first embodiment. The imageacquisition unit 21 acquires the radiographic image G0 as a detectiontarget (Step ST1) and the detection unit 22 detects a region of asurgical tool from the radiographic image G0 (Step ST2).

Then, the display control unit 23 determines whether or not the regionof the surgical tool has been detected from the radiographic image G0(Step ST3). In a case in which the determination result in Step ST3 is“Yes”, the display control unit 23 displays the radiographic image G0 inwhich the region of the surgical tool has been highlighted on thedisplay unit 6 (the display of the radiographic image in which thesurgical tool has been highlighted; Step ST4). Then, the process ends.On the other hand, in a case in which the determination result in StepST3 is “No”, the display control unit 23 notifies that the region of thesurgical tool has not been detected (notification that the surgical toolhas not been detected; Step ST5). Then, the process ends.

As described above, in the first embodiment, in a case in which theregion of the surgical tool is detected in the radiographic image G0 ofthe patient, the radiographic image G0 is displayed such that thedetected region of the surgical tool is highlighted. Here, theradiographic image G0 can be acquired in a state in which the patient isin the operating room. Further, since the radiographic image G0 is afluoroscopic image, it is easy to detect the surgical tool buried in thesurgical field, as compared to an image acquired by a camera. Therefore,according to this embodiment, it is possible to reliably prevent asurgical tool from remaining in the body of the patient after surgery,without imposing a burden on the patient.

Further, in the first embodiment, in a case in which the region of thesurgical tool is not detected in the radiographic image G0, the fact isnotified. Therefore, the operator can recognize that no surgical toolsremain in the body of the patient.

Next, a second embodiment of the present disclosure will be described.FIG. 11 is a diagram schematically illustrating the configuration of aradiographic image processing apparatus according to the secondembodiment implemented by installing, for example, a radiographic imageprocessing program according to the second embodiment in the console 2.In FIG. 11, the same components as those in FIG. 3 are denoted by thesame reference numerals and the detailed description thereof will berepeated. As illustrated in FIG. 11, the radiographic image processingapparatus according to the second embodiment differs from theradiographic image processing apparatus according to the firstembodiment in that it comprises an image processing unit 24 thatperforms image processing for checking a surgical tool on theradiographic image G0 to derive a processed radiographic image G1.

The image processing unit 24 performs the image processing for checkinga surgical tool on the radiographic image G0. Examples of the imageprocessing for checking a surgical tool include a process thatemphasizes the sharpness of the radiographic image G0 and a gradationconversion process that converts the gradation of the radiographic imageG0 in order to eliminate a blocked-up shadow in which a high-densitycomponent is saturated and a blown-out highlight in which a low-densitycomponent is saturated in the radiographic image G0.

In addition, in the second embodiment, the detection unit 22 may detectthe region of the surgical tool from the radiographic image G0 or maydetect the region of the surgical tool from the processed radiographicimage G1. Here, it is assumed that the region of the surgical tool isdetected from the radiographic image G0.

In addition, in the second embodiment, the radiographic image G0 and theprocessed radiographic image G1 are displayed as follows. FIG. 12 is aflowchart illustrating a process performed in the second embodiment. Theimage acquisition unit 21 acquires the radiographic image G0 as adetection target (Step ST11) and the display control unit 23 displaysthe radiographic image G0 on the display unit 6 (Step ST12). FIG. 13 isa diagram illustrating a display screen for the radiographic image G0.As illustrated in FIG. 13, the radiographic image G0 is displayed on adisplay screen 70. Further, a detection button 71 for receiving acommand to detect the region of the surgical tool is displayed on thedisplay screen 70. In addition, image processing for display may beperformed on the radiographic image G0. Further, in a case in which theradiographic image G0 includes the region of the surgical tool, theregion of the surgical tool may be checked in the displayed radiographicimage G0. However, in FIG. 13, the region of the surgical tool is notincluded in the radiographic image G0.

Next, in a case in which the detection button 71 is selected and acommand to detect the surgical tool is input from the input unit 7 (StepST13), the image processing unit 24 performs image processing forchecking a surgical tool on the radiographic image G0 (Step ST14).Further, the detection unit 22 detects the region of the surgical toolfrom the radiographic image G0 in response to the detection command(Step ST15). After the image processing for checking a surgical tool,the display control unit 23 displays the processed radiographic image G1on the display unit 6 (Step ST16). The process in Step ST15 is performedin parallel to the processes in Steps ST14 and ST16. However, theprocess in Step ST15 may be performed after Step ST14 or Step ST16. In acase in which the region of the surgical tool is detected from theprocessed radiographic image G1, the process in Step ST15 may beperformed in parallel to the process in Step ST16 after Step ST14 or maybe performed after Step ST16.

FIG. 14 is a diagram illustrating a display screen for a processedradiographic image. As illustrated in FIG. 14, the processedradiographic image G1 is displayed on a display screen 75 for aprocessed radiographic image. Here, the process of detecting the regionof the surgical tool requires a lot of time because the amount ofcalculation is large. Therefore, a progressive bar 76 indicating thatthe surgical tool detection process is being performed in the backgroundis displayed on the display screen 75. The operator can know from theprogressive bar 76 that the detection process is being performed in thebackground and the progress of the detection process. In a case in whichthe region of the surgical tool is included in the processedradiographic image G1, the displayed region of the surgical tool may bechecked in the displayed processed radiographic image G1. However, inFIG. 14, the region of the surgical tool is not included in theprocessed radiographic image G1.

In a case in which the detection process ends, the display control unit23 determines whether or not the region of the surgical tool has beendetected from the radiographic image G0 (Step ST17). In a case in whichthe determination result in Step ST17 is “Yes”, the display control unit23 displays the processed radiographic image G1 in which the region ofthe surgical tool has been highlighted on the display unit 6 (StepST18). Then, the process ends. On the other hand, in a case in which thedetermination result in Step ST17 is “No”, the display control unit 23notifies that the region of the surgical tool has not been detected(Step ST19). Then, the process ends.

FIG. 15 is a diagram illustrating a display screen for a processedradiographic image in which the region of the surgical tool has beenhighlighted. As illustrated in FIG. 15, a processed radiographic imageGH1 obtained by adding a frame 78 to the detected region of the surgicaltool in the processed radiographic image G1 to highlight the region ofthe surgical tool is displayed on a display screen 77. On the displayscreen 77, the progressive bar 76 indicates that the progress has beencompleted. In addition, instead of adding the frame 78, the region ofthe surgical tool may be masked or a mark may be added. Here, theprocessed radiographic image GH1 in which the region of the surgicaltool has been highlighted may be displayed on the display unit 6 bysuperimposing the frame 78 or the like on the processed radiographicimage G1. In addition, a process of adding a mask or the like may beperformed on the processed radiographic image G1 to separately generatethe processed radiographic image GH1 in which the region of the surgicaltool has been highlighted and the processed radiographic image GH1 maybe displayed on the display unit 6.

As described above, in the second embodiment, the image processing forchecking a surgical tool is performed on the radiographic image G0 andthe processed radiographic image G1 is displayed. Therefore, the regionof the surgical tool can be easily checked by the processed radiographicimage G1. Therefore, according to this embodiment, it is possible toreliably prevent a surgical tool from remaining in the body of thepatient after surgery in combination with highlighting the region of thesurgical tool.

In the second embodiment, the image processing for checking a surgicaltool is performed on the radiographic image G0 in response to thesurgical tool detection command. However, the present disclosure is notlimited to thereto. The image processing for checking a surgical toolmay be performed on the radiographic image G0 without waiting for thesurgical tool detection command or in response to a command for onlyimage processing.

In the second embodiment, in a case in which the detection command isinput, the processed radiographic image G1 and the processedradiographic image GH1 in which the region of the surgical tool has beenhighlighted are displayed on the display unit 6, instead of theradiographic image G0. However, the processed radiographic image G1 andthe processed radiographic image GH1 in which the region of the surgicaltool has been highlighted may be displayed on the display unit 6together with the radiographic image G0. FIG. 16 is a diagramillustrating a display screen on which the radiographic image G0 and theprocessed radiographic image GH1 in which the region of the surgicaltool has been highlighted are displayed together. FIG. 16 illustrates adisplay screen in a case in which the region of the surgical tool isdetected from the processed radiographic image G1. As illustrated inFIG. 16, the radiographic image G0 and the processed radiographic imageGH1 in which the region of the surgical tool has been highlighted aredisplayed on a display screen 80. In addition, FIG. 16 illustrates theprocessed radiographic image GH1 in which a frame 81 is added to thedetected region of the surgical tool to highlight the region of thesurgical tool. In FIG. 16, a frame or the like for highlighting theregion of the surgical tool is not displayed in the radiographic imageG0. However, the frame or the like for highlighting the region of thesurgical tool may be added to the radiographic image G0. In addition,the frame or the like for highlighting the region of the surgical toolmay be added only to the radiographic image G0. Further, imageprocessing for display may be performed on the radiographic image G0.

Next, a third embodiment of the present disclosure will be described.FIG. 17 is a diagram schematically illustrating the configuration of aradiographic image processing apparatus according to the thirdembodiment implemented by installing, for example, a radiographic imageprocessing program according to the third embodiment in the console 2.In FIG. 17, the same components as those in FIG. 3 are denoted by thesame reference numerals and the detailed description thereof will not berepeated. As illustrated in FIG. 17, the radiographic image processingapparatus according to the third embodiment differs from theradiographic image processing apparatus according to the firstembodiment in that a display unit 8 having a larger screen and/or ahigher resolution than the display unit 6 is connected to the console 2and the radiographic image G0 is displayed on both the display unit 6and the display unit 8.

The display unit 8 consists of, for example, a liquid crystal monitorand has a larger screen size than the display unit 6. For example, whilethe screen size of the display unit 6 is 14 to 15 inches, the screensize of the display unit 8 is 40 to 50 inches. The display unit 8 isattached to, for example, the wall of the operating room. The displayunit 8 may have the same size as the display unit 6 or may have a higherresolution than the display unit 6. For example, in a case in which theresolution of the display unit 6 is 1 megapixel, the resolution of thedisplay unit 8 may be 2 megapixels or 3 megapixels or more. The displayunit 8 may have a larger size and higher resolution than the displayunit 6.

Next, a process performed in the third embodiment will be described.FIG. 18 is a flowchart illustrating the process performed in the thirdembodiment. First, the image acquisition unit 21 acquires theradiographic image G0 as a detection target (Step ST21) and the displaycontrol unit 23 displays the radiographic image G0 on each of the twodisplay units 6 and 8 (Step ST22). The display screen 70 illustrated inFIG. 13 is displayed on the display unit 6. Further, the display screen70 may also be displayed on the display unit 8 or only the radiographicimage G0 may be displayed on the display unit 8. Further, imageprocessing for display may be performed on the radiographic image G0.

Next, in a case in which the detection button 71 is selected and asurgical tool detection command is input from the input unit 7 (StepST23), the detection unit 22 detects the region of the surgical toolfrom the radiographic image G0 (Step ST24). In this case, a progressivebar indicating the progress of the surgical tool detection process maybe displayed on the display screen 70.

In a case in which the detection process ends, the display control unit23 determines whether the region of the surgical tool has been detectedfrom the radiographic image G0 (Step ST25). In a case in which thedetermination result in Step ST25 is “Yes”, the display control unit 23displays the radiographic image G0 in which the region of the surgicaltool has been highlighted on the two display units 6 and 8 (Step ST26).Then, the process ends. On the other hand, in a case in which thedetermination result in Step ST25 is “No”, the display control unit 23notifies that the region of the surgical tool has not been detected(Step ST27). Then, the process ends. The notification may be displayedonly on the display unit 6, may be displayed only on the display unit 8,or may be displayed on both the display unit 6 and the display unit 8.

As described above, in the third embodiment, the radiographic image G0is displayed on the display unit 8 having a larger screen and/or ahigher resolution than the display unit 6. Therefore, the region of thesurgical tool can be easily checked by the radiographic image displayedon the display unit 8. Therefore, according to this embodiment, it ispossible to reliably prevent a surgical tool from remaining in the bodyof the patient after surgery in combination with highlighting the regionof the surgical tool.

Next, a fourth embodiment of the present disclosure will be described.FIG. 19 is a diagram schematically illustrating the configuration of aradiographic image processing apparatus according to the fourthembodiment implemented by installing, for example, a radiographic imageprocessing program according to the fourth embodiment in the console 2.In FIG. 19, the same components as those in FIG. 11 are denoted by thesame reference numerals and the detailed description thereof will not berepeated. As illustrated in FIG. 19, the radiographic image processingapparatus according to the fourth embodiment differs from theradiographic image processing apparatus according to the secondembodiment in that the display unit 8 having a larger screen and/or ahigher resolution than the display unit 6 is connected to the console 2and the radiographic image G0 and the processed radiographic image G1are displayed on both the display unit 6 and the display unit 8.

Next, a process performed in the fourth embodiment will be described.FIG. 20 is a flowchart illustrating the process performed in the fourthembodiment. The image acquisition unit 21 acquires the radiographicimage G0 as a detection target (Step ST31) and the display control unit23 displays the radiographic image G0 on the two display units 6 and 8(Step ST32). Then, the display screen 70 illustrated in FIG. 13 isdisplayed on the display unit 6. The display screen 70 may also bedisplayed on the display unit 8 or only the radiographic image G0 may bedisplayed on the display unit 8. Further, image processing for displaymay be performed on the radiographic image G0.

Next, in a case in which the detection button 71 is selected and asurgical tool detection command is input from the input unit 7 (StepST33), the image processing unit 24 performs image processing forchecking a surgical tool on the radiographic image G0 (Step ST34). Thedetection unit 22 detects the region of the surgical tool from theradiographic image G0 in response to the detection command (Step ST35).Further, after the image processing for checking a surgical tool, thedisplay control unit 23 displays the processed radiographic image G1 onthe two display units 6 and 8 (Step ST36). Then, the display screen 75illustrated in FIG. 14 is displayed on the display unit 6. The displayscreen 75 may also be displayed on the display unit 8 or only theprocessed radiographic image G1 may be displayed on the display unit 8.The process in Step ST35 is performed in parallel to the processes inSteps ST34 and ST36. However, the process in Step ST35 may be performedafter Step ST34 or Step ST36. In a case in which the region of thesurgical tool is detected from the processed radiographic image G1, theprocess in Step ST35 may be performed in parallel to the process in StepST36 after Step ST34 or may be performed after Step ST36.

In a case in which the detection process ends, the display control unit23 determines whether the region of the surgical tool has been detectedfrom the radiographic image G0 (Step ST37). In a case in which thedetermination result in Step ST37 is “Yes”, the display control unit 23displays the processed radiographic image G1 in which the region of thesurgical tool has been highlighted on the two display units 6 and 8(Step ST38). Then, the process ends. On the other hand, in a case inwhich the determination result in Step ST37 is “No”, the display controlunit 23 notifies that the region of the surgical tool has not beendetected (Step ST39). Then, the process ends. The notification may bedisplayed only on the display unit 6, may be displayed only on thedisplay unit 8, or may be displayed on both the display unit 6 and thedisplay unit 8.

As described above, in the fourth embodiment, the image processing forchecking a surgical tool is performed on the radiographic image G0 toderive the processed radiographic image G1 and the processedradiographic image G1 is also displayed on the display unit 8 having alarge screen and/or a high resolution. Therefore, the region of thesurgical tool can be easily checked by the processed radiographic imageGH1 in which the region of the surgical tool has been highlighted andwhich is displayed on the display unit 8. Therefore, according to thisembodiment, it is possible to reliably prevent a surgical tool fromremaining in the body of the patient after surgery in combination withhighlighting the region of the surgical tool.

In the fourth embodiment, the image processing for checking a surgicaltool is performed on the radiographic image G0 after the surgical tooldetection command is input. However, the present disclosure is notlimited thereto. The image processing for checking a surgical tool maybe performed on the radiographic image G0 without waiting for thesurgical tool detection command or in response to a command for onlyimage processing.

Further, in the fourth embodiment, in a case in which the detectioncommand is input, the processed radiographic image G1 is displayed onthe display units 6 and 8, instead of the radiographic image G0.However, the radiographic image G0 and the processed radiographic imageG1 may be displayed together on the display units 6 and 8.

In each of the above-described embodiments, the turn-on and turn-off ofthe highlight display of the radiographic image G0 and/or the processedradiographic image G1 may be switched in response to a command from theinput unit 7.

Further, in the above-described embodiments, the radiographic image G0and/or the processed radiographic image G1 in which the region of thesurgical tool has been detected may be transmitted to an externalapparatus such as the PACS 101. In this case, information indicatingthat the region of the surgical tool has been detected may be given tothe radiographic image G0 and/or the processed radiographic image G1.For example, in a protocol such as digital imaging and communication inmedicine (DICOM) that defines the storage format of image data andcommunication between apparatuses, various kinds of information may begiven as accessory information to the radiographic image G0 and/or theprocessed radiographic image G1. Therefore, the DICOM protocol may beused to give information indicating that the region of the surgical toolhas been detected to the accessory information of the radiographic imageG0 and/or the processed radiographic image G1. Further, a process ofadding a frame or the like for highlighting the region of the surgicaltool may be performed on the radiographic image G0 and/or the processedradiographic image G1 to generate the radiographic image GH0 and/or theprocessed radiographic image GH1 in which the region of the surgicaltool has been highlighted and the generated radiographic image GH0and/or processed radiographic image GH1 may be transmitted to anexternal apparatus.

Further, in each of the above-described embodiments, the console 2performs, for example, the surgical tool detection process and the imageprocessing. However, the present disclosure is not limited thereto. Forexample, the radiographic image processing program according to each ofthe embodiments of the present disclosure may be installed in the PACS101 illustrated in FIG. 2. The radiographic image G0 acquired by theconsole 2 may be transmitted to the PACS 101 and the PACS 101 mayperform a process of detecting the region of the surgical tool from theradiographic image G0 or may perform image processing for checking asurgical tool. In this case, the PACS 101 may perform the process ofadding a frame or the like for highlighting the region of the surgicaltool on the radiographic image G0 and/or the processed radiographicimage G1 to generate the radiographic image GH0 and/or the processedradiographic image GH1 in which the region of the surgical tool has beenhighlighted and transmit the generated radiographic image GH0 and/orprocessed radiographic image GH1 to the console 2. Further, the PACS 101may give information indicating that the region of the surgical tool hasbeen detected to the accessory information of the radiographic image G0and/or the processed radiographic image G1 and transmit the accessoryinformation to the console 2, using the DICOM protocol. In this case,the console 2 performs the process of highlighting the region of thesurgical tool included in the radiographic image G0 and/or the processedradiographic image G1 on the basis of the accessory information anddisplays the radiographic image GH0 and/or the processed radiographicimage GH1 in which the region of the surgical tool has been highlightedon the display units 6 and 8. In this case, it is possible to switch theturn-on and turn-off of the highlight display.

Further, in the second and fourth embodiments, the degree of imageprocessing for the displayed processed radiographic image G1 may bechanged. For example, the degree of emphasis of the sharpness and thedegree of change of the gradation of the processed radiographic image G1may be changed. In this case, it is possible to display the processedradiographic image G1 with the desired quality on the display unit 6and/or the display unit 8.

Further, in each of the above-described embodiments, the detection unit22 detects the region of the surgical tool using the discriminator 30.However, the present disclosure is not limited thereto. A histogram ofthe radiographic image G0 may be calculated and it may be determinedwhether or not a signal value of the surgical tool is included in thehistogram to detect the region of the surgical tool from theradiographic image G0 or the processed radiographic image G1.

In each of the above-described embodiments, the radiographic image G0 isa still image. However, the present disclosure is not limited thereto.The radiographic image G0 may be a moving image. In this case, theprocess of detecting the region of the surgical tool is performed oneach frame of the radiographic image G0 which is a moving image.

In each of the above-described embodiments, the radiographic image G0 ofthe subject H is acquired by the radiation source 4 and the radiationdetector 5. However, the present disclosure is not limited thereto. Forexample, in some cases, the operator performs surgery while observingthe radiographic image G0 of the patient using a C-arm fluoroscopicapparatus. In this case, the radiographic image G0 may be acquired bythe C-arm fluoroscopic apparatus.

In the above-described embodiments, the gauze 40 as a surgical tool is adetection target. However, the present disclosure is not limitedthereto. Any surgical tools, such as a scalpel, scissors, a drain, aneedle, a thread, and forceps, which are used during surgery and shouldnot remain in the body may be used as the detection targets. In thiscase, the discriminator 30 may be trained so as to discriminate thetarget surgical tool. The discriminator 30 is trained so as to detect aplurality of channels, which makes it possible to construct thediscriminator 30 so as to discriminate not only one kind of surgicaltool but also a plurality of kinds of surgical tools.

In addition, in the above-described embodiments, the radiation is notparticularly limited. For example, α-rays and γ-rays other than X-rayscan be applied.

In the above-described embodiments, for example, the following variousprocessors can be used as a hardware structure of processing unitsperforming various processes, such as the image acquisition unit 21, thedetection unit 22, the display control unit 23, and the image processingunit 24. The various processors include, for example, a CPU which is ageneral-purpose processor executing software (program) to function asvarious processing units, a programmable logic device (PLD), such as afield programmable gate array (FPGA), which is a processor whose circuitconfiguration can be changed after manufacture, and a dedicated electriccircuit, such as an application-specific integrated circuit (ASIC),which is a processor having a dedicated circuit configuration designedto perform a specific process.

One processing unit may be configured by one of the various processorsor a combination of two or more processors of the same type or differenttypes (for example, a combination of a plurality of FPGAs or acombination of a CPU and an FPGA). Further, a plurality of processingunits may be configured by one processor.

A first example of the configuration in which a plurality of processingunits are configured by one processor is an aspect in which oneprocessor is configured by a combination of one or more CPUs andsoftware and functions as a plurality of processing units. Arepresentative example of this aspect is a client computer or a servercomputer. A second example of the configuration is an aspect in which aprocessor that implements the functions of the entire system including aplurality of processing units using one integrated circuit (IC) chip isused. A representative example of this aspect is a system-on-chip (SoC).As such, various processing units are configured by using one or more ofthe various processors as the hardware structure.

Furthermore, specifically, an electric circuit (circuitry) obtained bycombining circuit elements, such as semiconductor elements, can be usedas the hardware structure of the various processors.

What is claimed is:
 1. A radiographic image processing apparatuscomprising at least one processor, wherein the processor is configuredto: detect a region of a surgical tool in a radiographic image of apatient; and in a case in which the surgical tool is detected, displaythe radiographic image in which the detected region of the surgical toolhas been highlighted on a display.
 2. The radiographic image processingapparatus according to claim 1, wherein the processor is furtherconfigured to: perform image processing for checking the surgical toolon the radiographic image to derive a processed radiographic image. 3.The radiographic image processing apparatus according to claim 2,wherein the radiographic image in which the detected region of thesurgical tool has been highlighted and which is displayed on the displayis the processed radiographic image.
 4. The radiographic imageprocessing apparatus according to claim 2, wherein the processor isconfigured to display, on the display, the radiographic image before theimage processing for checking the surgical tool, derive the processedradiographic image and the start a process of detecting the region ofthe surgical tool in response to a command to detect the region of thesurgical tool, in a case in which the processed radiographic image isderived, display the processed radiographic image on the display,instead of the radiographic image before the image processing ortogether with the radiographic image before the image processing, andafter the process of detecting the region of the surgical tool ends,display the radiographic image in which the region of the surgical toolhas been highlighted on the display.
 5. The radiographic imageprocessing apparatus according to claim 1, wherein the processor isconfigured to display the radiographic image in which the detectedregion of the surgical tool has been highlighted on another display thathas a larger size and/or a higher resolution than the display.
 6. Theradiographic image processing apparatus according to claim 4, whereinthe processor is configured to display the radiographic image before theimage processing, the processed radiographic image, and the radiographicimage in which the detected region of the surgical tool has beenhighlighted on another display that has a larger size and/or a higherresolution than the display.
 7. The radiographic image processingapparatus according to claim 1, wherein the processor is configured to,in a case in which the surgical tool is not detected, notify the fact.8. The radiographic image processing apparatus according to claim 1,wherein the radiographic image is acquired by a portable radiationdetector or an imaging apparatus that is installed in an operating roomfor performing surgery on the patient.
 9. The radiographic imageprocessing apparatus according to claim 1, wherein the processor isconfigured to discriminate the region of the surgical tool in an inputradiographic image by a discriminator trained so as to discriminate theregion of the surgical tool in the input radiographic image.
 10. Theradiographic image processing apparatus according to claim 1, whereinthe surgical tool includes at least one of gauze, a scalpel, scissors, adrain, a needle, a thread, or forceps.
 11. The radiographic imageprocessing apparatus according to claim 10, wherein at least a portionof the gauze includes a radiation absorbing thread.
 12. A radiographicimage processing method comprising: detecting a region of a surgicaltool in a radiographic image of a patient; and in a case in which thesurgical tool is detected, displaying the radiographic image on adisplay such that the detected region of the surgical tool ishighlighted.
 13. A non-transitory computer-readable storage medium thatstores a radiographic image processing program that causes a computer toperform: detecting a region of a surgical tool in a radiographic imageof a patient; and in a case in which the surgical tool is detected,displaying the radiographic image on a display such that the detectedregion of the surgical tool is highlighted.